US Vice President Mike Pence spoke during a meeting in the NATO summit on Wednesday and called on Turkey to step back regarding the S-400 aerial defense system.

Turkish Foreign Minister Mevlut Cavusoglu spoke in another meeting in Washington and said, “The deed is done, we won’t step back” regarding the S-400 system bought from Russia.

PENCE: TURKEY MUST CHOOSE

Shortly after, Mike Pence posted a harsh statement on Twitter and said:

“Turkey must choose. Does it want to remain a critical partner in the most successful military alliance in history or does it want to risk the security of that partnership by making such reckless decisions that undermine our NATO alliance?”

Turkish Vice President Fuat Oktay issued a new statement on Thursday, copying and reversing the US statement: “The US must choose. Does it want to remain Turkey’s ally or risk our friendship by joining forces with terrorists to undermine its NATO ally's defence against its enemies?”

US OFFICIALS: THERE IS NO MIDDLE GROUND

According to Voice of America radio, Cavusoglu also met with US House of Representatives Foreign Affairs Commission Chair Democrat Eliot Engel and senior member of the commission Republican Michael McCaul during his time in Washington.

Engel and McCaul issued a written statement after the meeting and said there is clear opposition from both sides of the aisle to Turkey’s plans to purchase Russian-made S-400 missile systems that could endanger the country’s participation in NATO.

The statement said Minister Cavusoglu was presented with a generous offer to purchase Patriot missiles that can work with NATO instead of the S-400s, and stressed that there is no middle ground in Turkey choosing defense cooperation with both Russia and the US.

The statement also said the Turkish government should choose to show their loyalty to the NATO alliance, as the deepening of the ties with Moscow puts Turkey at risk in regards to sanctions and participation in the F-35 program.

F-35 FIGHTER JET PROJECT AFFECTED

The tensions between the US and Turkey regarding the S-400 missile system has risen in the last few days. On April 2, Reuters published an article that they based on 2 sources that said US officials informed their Turkish counterparts that the delivery of equipment related to the F-35 fighter jet project was paused.

The decision was seen as the first concrete step by the US against Ankara purchasing S-400 aerial defense systems from Russia.

The F-35 is manufactured by the American weapons giant Lockheed Martin, and some parts are sourced from Turkey.

American sources who wish to remain anonymous said delivery for the training equipment and all F-35 related materials have been cancelled for the future.

The US and other NATO allies that have F-35 jets are concerned about the S-400 systems, especially for Russia to learn how to detect and surveil F-35 jets with the S-400 missile defense system and that these jets will be more vulnerable against Russian-made weapons in the future.